The present invention relates generally to parametric audio amplifier systems for generating airborne audio signals, and more specifically to a parametric audio amplifier system that employs a low voltage connection between an amplifier assembly and an acoustic transducer assembly.
Parametric audio amplifier systems are known that employ an acoustic transducer for projecting an ultrasonic carrier signal modulated with a processed audio signal through the air for subsequent regeneration of the audio signal along a selected path of projection. A conventional parametric audio amplifier system includes a modulator configured to modulate an ultrasonic carrier signal with a processed audio signal, a driver amplifier configured to amplify the modulated carrier signal, and at least one acoustic transducer configured to project a sonic beam corresponding to the modulated ultrasonic carrier signal through the air along a selected projection path. Because of the nonlinear propagation characteristics of the air, the projected sonic beam is demodulated as it passes through the air to regenerate the audio signal along the selected projection path.
One drawback of the conventional parametric audio amplifier system is that the acoustic transducer included therein is typically driven by the driver amplifier with a high voltage signal, which may be on the order of hundreds of volts. In contrast, a conventional loudspeaker is typically driven with a relatively low voltage signal of about 50 volts. For this reason, a high voltage connection configured to carry such high voltage signals is typically employed in the conventional parametric audio amplifier system to interconnect the driver amplifier and the acoustic transducer.
However, the use of high voltage connections in parametric audio amplifier systems can be problematic because such connections typically comprise specialized high voltage cables and/or connectors, which can significantly increase the size and cost of the system. Further, such high voltage cabling must typically conform to cable routing requirements that are more stringent than that of low voltage cabling used in conventional loudspeaker systems. As a result, special considerations must often be made when installing high voltage cabling for parametric audio amplifier systems, which can significantly increase the cost and complexity of the installation.
It would therefore be desirable to have a parametric audio amplifier system that has both reduced size and cost. Such a parametric audio amplifier system would be configured to be conformable to cable routing requirements that are no more stringent than that of conventional loudspeaker systems.